Slope Calculator
Calculate the slope between two points.
How this calculator works
How to use this calculator
1. Enter x₁ and y₁ for the first point.
2. Enter x₂ and y₂ for the second point.
3. Click Calculate Slope.
4. The calculator shows the rise divided by the run, or Undefined for a vertical line.
Formula used
Slope = (y₂ − y₁) ÷ (x₂ − x₁)
The numerator is the rise and the denominator is the run. If x₂ − x₁ = 0, the line is vertical and its slope is undefined.
Example calculation
Example: (1, 2) and (5, 10)
Rise = 10 − 2 = 8
Run = 5 − 1 = 4
Slope = 8 ÷ 4 = 2
What the result means
Slope describes how much y changes for each one-unit change in x. Positive slope rises from left to right, negative slope falls, zero slope is horizontal, and a vertical line has undefined slope.
Frequently asked questions
Why can slope be undefined?
A vertical line has zero horizontal change, so the formula would require division by zero.
Can slope be a decimal?
Yes. Slope can be positive, negative, zero, a fraction, or a decimal.
Does the order of the two points matter?
No, as long as the same point order is used in both the numerator and denominator.